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Busybee

Centre gravity

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So I’m at centre gravity tomorrow with Shirley. Finally bitten the bullet and accepted she needs a really good set up. The current setup just doesn’t do it for me. Soft, skittish, bouncy. All terms I’d use to describe the current feel if the car when making progress.

Not sure what to expect. I’m a CG virgin. Having the full days treatment. Assessment, ride height, geo, inspection..... 

Thought I’d document my experience here in case anyone new is interested in doing this. 

Shirley is bone stock except for koni shocks in place of the original boge. 

Any advice from old hands? 

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I'm guessing, turn up, hand the keys over, find something to do for 8 hours (or watch), go back, ask what they did, drive home, revel in the delight of a newly set up car.

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17 minutes ago, Phill said:

I'm guessing, turn up, hand the keys over, find something to do for 8 hours (or watch), go back, ask what they did, drive home, revel in the delight of a newly set up car.

Get involved. Watch everything he does. Buy the bacon sandwiches at lunch time 😎

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I watched when I had mine done (not at CG) and it is very interesting if you are as spannerer but wouldn't be if you aren't. Not sure about paying for lunch when you are a paying customer, shouldn't it be the other way round?

Whichever, it will be a good day for you Haith.

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I had mine done by Chris at Centre Gravity in 2016. I was amazed at the difference he made. He’s a really nice guy who knows his stuff. 

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Best money I have spent on any car ever. But be prepared for a long wait (8 hours? I was there for 12 hours on a Friday too) Chris will not hand the car back to you until he is completely happy. Even at 8pm of a Friday after working for 12 hours, he went through the hand over process of him driving then me driving while he walked through all the differences from before. My car was way way off and he had to re-index a couple of torsion bars twice to get everything right so you might be luckier.

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Get involved with watching what’s done.  I found it fascinating when he worked on mine, although I can’t say I understood it all.  As said, Chris will work late to do a thorough job until he’s happy with it.  Be prepared to describe how you want the car set up - ride height etc. 

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So @Busybee Haith, how did you get on, or are you still there?

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I'm back! Less bouncy and a lot more planted. Full report to follow but Chris was done by about 6pm last night. Early finish for him by the sounds of it. Catch up on work then I'll bore you to tears with tales of toe (not a camel in sight!) 

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Cleared my desk. A little round up.

ASSESSMENT

Arrived 8.30am (if you're travelling to CofG from afar, the Abbey Farm B&B up the roads is recommended) Quick chat then straight in the car for a test drive. Chris drove while I told him my suspension woes. Basically the car felt a bit unpredictable. Would catch a camber and veer off but sometimes right other times left. Also jittery and felt like it was skipping off faster bumps. 

Back to HQ and straight on the damper tester. All corners were good with an absorption theta of 0.3 (no idea what that is but Chris said its good)

Then up on the ramp and the Hawkeye machine and manual measurements of each corner for tread depth, pressures, ride height, rake angle, corner weight. It was all over the shop. 

The rake (angle of the sills front to back) was 1.8 degrees (factory 0.5-0.8 deg). The factory is a little "safe" but 1.8 was too high.

The toe out on the front wheels was out and different both sides. This accounted in part to the tendency to pull away from straight in either direction and to try to pull to one side under thrust. This was probably the biggest problem he found. Little more wear on the inside of the front tyres due to this.

Also, diagonal corner weights were different by 28kg. So chuck it into a right hander and it would behave differently and require different braking to a left hander.

Ride height was lower than factory at around 2 fingers top of tyre to arch. We'll get to that.

Rear was very good but just too stiff. 

Chris then inspected every rubber bush in the steering and suspension. All good.

We chatted about how I'd want the ride height and feel. We decided on taking off about 20mm and making the ride height one finger top of tyre to arch. 

PROCESS

Chris got to work.

Starting at the front, took each damper out and measured them for stiffness (I'd set these at half a turn off fully stiff thinking that would give me the sporty ride I was after). There was a little variation between the fronts. 1/4 turn. The rears were set at the same and they were spot on. 3 out of 4 isn't bad lol. Chris reset all damper stiffness's to 2 turns out. there is 3.5 turns on the koni classic from fully stiff to fully soft. Hugely different to my settings. He also changed my top mounts for good second hand ones off his car (FOC) as mine had the big Koni rubbers I put in instead of leaving my good Porsche rubbers in place - doh!)

He then lowered the front to the 1 finger we'd agreed.

Then he moved onto the rears. Again, he reset the dampers but this time to -1 3/4 turns from FFS. Set the ride height on the spring plates (experience here - basically, he drew a line in the centre of the plate as it was set dead centre and dropped the rear section so it just touched the fixed line. 1 finger.

Back on the hawkeye and it was better but not spot on. He fiddled a couple of more times to make sure the ride height and camber at the back was spot on. 

Back to the front and he set the toe. Also set the caster for a fast slalom setup. Handy for Welsh roads right. Camber is what you end up with with the other two set where you want but it's not bad apparently

RESULTS 

Well its a huge difference. Tracks true and straight (unsurprisingly). Rides over the bumps as a glide rather than bumps unsettling it and throwing it off line. Softer but it feels like its digging in in the corners under throttle. That combined with the greater predictability saw me going down a bumpy B road on the same test circuit as the morning, 50% faster in the afternoon (read into that what you will officer). Plus it felt chuckable. Steering is noticeably lighter.

3 hour drive home in the rain and I'm sure I was as fast in the rain as I was in the dry going up. With absolutely no dramas. It actually felt like I had to relearn the steering character of the car as there were corners where I thought I could have carried much more speed there. 

The motorway section was definitely more enjoyable. Softer plusher ride and I had to concentrate on keeping speed down. The day before going up, it felt jittery and unsettled.

I'm still not 100% sold on the Koni's but if you're after a plush ride, think you'll love them.

I'm going to drive my SC and the 3,2 back to back in the next few days to compare the Bilsteins with the set up Koni's before I draw a firm conclusion. 

It's much, much better and far more tractable and predictable and that's from 3 hours driving home in the rain. Chris did say, the Konis don't have the high pressure nitrogen inserts so will always behave differently.

Think Chris and Pete know their work very well. They want you involved and explain every process. Never felt under foot. They took around 9 hours with my car. A day well spent and I can't wait to drive her on my usual roads to feel the difference. 

Setup Before.jpg

Setup After.jpg

before height.jpg

After Ride Height.jpg

Corner weights before P.jpg

Corner Weights After P.jpg

65319524_10219442500680975_5506061663024971776_n.jpg

65009793_10219442501360992_6593790889837985792_n.jpg

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42 minutes ago, Busybee said:

Cleared my desk. Snuffed out some candles and wiped up some wax....

Excellent write up. Thanks for that. I think I will get mine done again, soon.

How much was it?

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1 hour ago, Phill said:

Excellent write up. Thanks for that. I think I will get mine done again, soon.

How much was it?

Snuffed out some candles and wiped up some wax....  😂 welcome to my world. More like sorted problem, another landed......

If he's done yours and you've not changed anything you won't need to do it again. Obs if you've changed stuff.....

£680 inc VAT 

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Hardly gone up in a decade = bargain :twocents:

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Just now, Dr Rock said:

Hardly gone up in a decade = bargain :twocents:

Thought I might see you there Doc

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Nice work Haith!

Have to admit, if someone asked me how I’d like my car to feel, id struggle to describe it.

Adjectives like “Grrr-eat” and “Triffic” would not help matters, I feel?

Which makes me wonder if I’d appreciate the benefit, especially if i don’t know what’s ‘wrong’.

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1 minute ago, SP72 said:

Nice work Haith!

Have to admit, if someone asked me how I’d like my car to feel, id struggle to describe it.

Adjectives like “Grrr-eat” and “Triffic” would not help matters, I feel?

Which makes me wonder if I’d appreciate the benefit, especially if i don’t know what’s ‘wrong’.

Best to tell them what you don't like and let them fix that Shirish. It is a huge difference from before and after and really down to erroneous settings or part changes without calibration over the years..

Your car is pretty sorted anyway isn't it mate? 

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19 minutes ago, Busybee said:

Thought I might see you there Doc

You picked the wrong day :doh2:

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6 minutes ago, Busybee said:

And the track car that he uses as an everyday car even in winter (with winters). Hard core. Think he said it was 917kg

https://www.dropbox.com/s/6umqycc07tweqqb/WhatsApp Video 2019-06-26 at 14.34.00.mp4?dl=0

Chris is at the Oulton RS day every year in that thing, great car and plenty smiles per mile.

Pleased you got a result BB, hope you enjoy feeling more confident in your car.

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22 minutes ago, Busybee said:

Best to tell them what you don't like and let them fix that Shirish. It is a huge difference from before and after and really down to erroneous settings or part changes without calibration over the years..

Your car is pretty sorted anyway isn't it mate? 

It’s got all the bits on it (maybe some KWs would be nice), but probably needs setting up - it’s a collection of parts right now.

I can’t differentiate between a good and bad setup, hence me hesitating about spending £500+ on alignment etc when right now feels ok. (rightly or wrongly)

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21 minutes ago, SP72 said:

It’s got all the bits on it (maybe some KWs would be nice), but probably needs setting up - it’s a collection of parts right now.

I can’t differentiate between a good and bad setup, hence me hesitating about spending £500+ on alignment etc when right now feels ok. (rightly or wrongly)

You're welcome to have a go in mine sometime (once I've swapped out some fuel lines) and see what you think. 

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11 minutes ago, Northy said:

You're welcome to have a go in mine sometime (once I've swapped out some fuel lines) and see what you think. 

That could be an option Lewis thanks - you can drive mine and see what you think too

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1 hour ago, Busybee said:

Snuffed out some candles and wiped up some wax....  😂

£680 inc VAT 

Goodness me! I paid £250 (but not at CG) probably 5 years ago. I think I shall remain happy with what I've got.........

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